820-2915 no power

[borderhunter]

isl6259 new changed

ppbus_h3h is 1.35v
pp3v42_g3h 3.476
SMC_RESET_L - 3.3V

 

[G.Beard]

History?

Chacked for bad caps?

Checked all inductors for shorts... Even those that have nothing to do with PPBUS?

Does PPBUS start high and ramp down?

 

[borderhunter]

This is board water damage
r7021/22 change
PPBUS start high and ramp down Yes.1.35v,1.63v,1.71v

 

[G.Beard]

This is board water damage
r7021/22 change
PPBUS start high and ramp down Yes.1.35v,1.63v,1.71v

Check current sensing. If nothing wrong, try all other inductors for shorts.
Had the same issue recently. Turned out to be a short on Q7330.

What is resistance to ground on PPBUS?

 

[dukefawks]

The usual measurements, resistance between pins 17/18, 27/28 of U7000. If ok then check R7005. Resistance to GND on PPBUS? I assume green light is present.

 

[borderhunter]

Yes I have a green light..Pins 17/18 1.438v
27/28 16.76v

 

[aprendiz]

Read the post from Dukefawks...

resistance between pins 17/18, 27/28 of U7000. If ok then check R7005. Resistance to GND on PPBUS? I assume green light is present.

 

[borderhunter]

I check r7005 25.6 ohm

 

[dukefawks]

I ask resistance.....

 

[borderhunter]

Sorry.My english little.I check now resistance between pins 17/18, 27/28 of U7000 ok
And R7005 ok strong.
U7000 around resistance strong

 

[dukefawks]

Uhm,,,,"ok" is not a value.